Lubricant



Patented Aug. 21, 1934 LUBRICANT Lawrence C. Brunstrum, Chicago, 111.,and Daniel G. Loetscher, Whiting, Ind., assignors to Standard OilCompany, Chicago, III., a corporation of Indiana No Drawing.

'14Claims.

Ihis invention relates to lubricants and it pertains more particularlyto plug valve lubricants.

An object of our invention is to provide a lubri- I cant for plug valveswhich will be insoluble in oils, gasoline, benzene, carbontetrachloride, ether, etc. This lubricant must not only be insoluble inthe liquids with which it comes in contact, but it must tenaciouslyadhere to the valve and seal it, the property of forming a permanentseal being of the utmost importance. The lubricant must, however, allowthe valve to be turned at the temperatures for which it is designed. Itis also desirable that the material be non-corrosive, stable, and easilyhandled. An object of our invention is to provide a valve lubricanthaving all these properties.

We have discovered that salts of alginic acid are remarkably effectivein giving the desired properties to valve lubricants. For instance, acomposition of sodium alginate in a polyhydric alcohol such as glycerinor'glycol is insoluble in all of the solvents above mentioned, it formsan excellent valve seal, and it does not decompose when it is boiledwith naphtha for upwards of seven hours. The composition will not melteven when heated almost to its burning temperature, it will notdisintegrate, it may be easily handled and its consistency facilitateseasy valve operation throughout the entire temperature range.

Furthermore, the alginate compositions are so inert and non-corrosivethat they may be easily handled and are more beneficial than detrimentaltothe skin. They may be used generally as protective coatingcompositions against gasoline, carbon tetracholoride, ether, etc.

This invention will be more clearly understood from the followingspecific formula:

Percent Sodium alginate 19.0 Glycerin 76.0 Water 5.0

The sodium alginate cannot be mixed directly with the qlyhydric alcoholbut we have discovered thatit may be incorporated therein by flrstmaking an aqueous paste. The sodium alginate is mixed with an excess ofwater, using about 10 to 15% alginate to 85 or 90% water.

Any suitable mixer may be used and the temperature may be anywhere fromordinary room temperature to the boiling point of water, hightemperatures being generally preferred. The

sodium alginate may be in flake form or in the .of the mixture.

Application December 31, 1931, Serial No. 584,276

finely'divided amorphous powder form and when it is incorporated inwater it yields a yellowish orange mass which resembles glue inappearance, but which may be readily worked between the fingers likegrease. When the alginate has been completely dispersed in water we addthe poly hydric alcohol and boil the undesired water out The polyhydricalcohol should,

of course, be thoroughly mixed with the aqueous paste, prior to theremoval of water. When the 55 proportions are approximately those givenin the above formula, the mass may be forced through an orifice to formsticks which may be coated. with powdered mica to facilitate handling.These sticks will be as flexible as soft rubber so that they may beeasily rolled into spirals or packed into any desired shipping cartons.The material may be easily worked into a. paste-like consistency,however, and when it is applied to valves it adheres thereto evenly andtenaciously and at the same time allows the valves to be turned freely.

The amount of sodium alginate in our composition may be as high as 20 to25% but if 25% is used and the water is removed from the paste, theresulting mass will be too hard for general use. Ordinarily we preferfrom 5 to 20% .of sodium alginatef A hard lubricant being described inthe above example,- and a soft lubricant being as follows:

- Percent Sodium alginate 7.2 Polyhydric alcohol 82.8 Water 10 Thislubricant is made up in the same manner as the first mentionedlubricant; the sodium alginate is made up into a 10 or 15% aqueouspaste, the paste is mixed with the polyhydric alcohol and excess wateris boiled oil". This formula yields a lubricant which must be handledlike a cup grease but it has the same general properties as the sticklubricant above described.

These lubricants are absolutely unaffected by gasoline, naphtha, benzol,and carbon tetrachloride and they may also be used with chloroform,ether, toluene or monolchlor benzene. If an irregular mass of thelubricant is placed in a flask of boiling naphtha and boiled for 6 or 8hours the mass does not change shape, the naphtha is not discolored andthe lubricant has exactly the same properties as it had before beingsubjected to this test. Furthermore, the lubricant may be heated almostto the burning temperature, without melting and even under this severe Ytest it does not disintegrate. Even the hard compositions may be readilyworked and applied to valves and-when so applied they form permanenttight seals which are not impaired by time, temperature, or continueduse.

While we prefer to use the sodium alginateglycerin composition abovedescribed we do not limit ourselves thereto and we may incorporate thealginate in other media, in much the same manner as it is incorporatedin glycerin. We may use other salts of alginic acid, especially alkalimetal salts like potassium alginate. It is practically impossible toremove all of the water from the above compositions and usually it issufiicient if the water content be reduced to about 5 or We prefer,however, when possible to carry the water content even lower. The hardlubricant is preferably cast into blocks and then, at about roomtemperature, it is forced through the orifice or die to form sticks, butit is obvious that other forms of the lubricant may be used. We do notlimit ourselves to the details above set forth except as defined by thefollowing claims, which should be construed as broadly as the prior artwill permit.

We claim:

1. A composition of matter consisting essentially of a salt of alginicacid incorporated in a polyhydric alcohol.

2. A com 'tion of matter consisting essentially of a salt of alginicacid incorporated in glycenn.

3. A method of incorporating a salt of alginic acid in a substantiallynon-aqueous medium which comprises making a paste of the alginic saltsin water, mixing said paste with the nonaqueous medium, andsubstantially dehydrating the mixture.

4. A lubricant consisting essentially of a small amount, not more than25%, of an alginic acid salt incorporated in a polyhydric alcohol. Y

5. A composition of matter consisting essential y of sodium alginate, aand a small amountof water.

6. A composition of matter consisting essentially of sodium alginate,glycerin, and a small amount of water.

p yhydric alcohol,

7. A lubricant consisting essentially of about 5 to 20% sodium alginate,'75 to p lyhwdric alcohol and about 1 to 10% water.

8. A lubricant consisting essentially of a stick of a sodium alginatepolyhydric alcohol composiin'on coated with an inert powder.

9. A lubricant consisting essentially of a stick of a sodium alginatepolyhvdric alcohol composition coated with a powdered mica.

10. A composition of matter consisting essentially of a salt of alginicacid incorporated in glycol. A

11. A composition of matter consisting essentially of sodium alginate,glycol, and a small amount of water.

12. A non-corrosive valve lubricant which is insoluble in oils,gasoline, benzene, carbon tetrachloride and ether, which willtenaciously adhere to a valve and seal it and which will allow the valveto be turned, which valve lubricant comprises a pasty composition whichwill not melt when heated almost to its burning temperature, which willnot disintegrate, and which is characterized by approximately thefollowing formula:

Sodium alginate 5 t0 20%. Glycerine 75 to 90%. Water 1 to-10%.

13. A plug valve lubricant which is insoluble in oil, gasoline, benzene,carbon tetrachloride and ether and which has the properties of adheringto and sealing a valve and yet allowing the valve to be freely operatedthroughout a wide tempera--

